Osteoclast are multinucleate bone resorbing cells derived from the haemopoietic stem cell. An osteoclast is about 30-100μ in size and has multiple discrete oval nuclei. They have azurophilic granules. The megakaryocyte though a large cell, unlike an osteoclast, normally has a single multi-lobed nucleus. Osteoclasts are truly multinucleate. The azurophilic granules of osteoclasts are coarser.